The letter relates to events growing out of the Kirov assassination, Dec. 1 1934, and the circumstances surrounding the Zinoviev-Kamenev-Smirnov trial of August 1936, and the Radek-Piatakov trial of January 1937. It appeared first in two parts in the Socialist messenger, Dec. 22, 1936 and Jan. 17, 1937. It was published subsequently in several languages in the information bulletin of the Labor and socialist international. The translation published here was specially prepared from the Russian original. 

Translator's preface. Samuel A. Portnoy

Letter of an Old Bolshevik: A Key to the Moscow Trials